Borehole and other pumps



Patented May 21, 1929.

HEB-MANN KNAB, F NUREMBERG, GERMANY, ASSIGNOR OF ONE- HALF TO PHILIPPE I SCH 'JLER, OF LAUSANN E, SWITZERLAND.

BoREnoLE AND OTHER PUMPS.

Application filed June 27, 1927, Serial No.

g system of valve gear of hydraulically operated pumps is not completely positive, and therefore ol'ten fails, the pumps being, consequently, unsuitable for lowering into deep boreholes. According to the lllYBIltion, this defect is remedied by the use ot positively operated valve gear, which enables the pump to be started in any position of the plunger. v

An embodiment of the sub e"t of the mvention is illustrated in the drawing, Figure 1, representing a cross section and Figure 2a longitudinal section of the pump along the line 11-11 of-Figure 1.

Figure 3 is an enlarged detail sectional view of the actuator or sleeve carried by the main piston stem. 4

Figure 4 is a cross-section taken on line 44 of Figure 3.

The body of the pump is cylindrical and contains a cylindrical working chamber 1, for the interconnected working plungers 2, 3, with the delivery pistons 4, 5, which project into the cylindrical working chambers 6, 7. 25 By means of passages 46, 45, the working chambers 6, 7 are connected with valve chambers 47, 48, containing the non-return valves 51, 52 and 49, 50 respectively and the passages 53, 56 and 54, 57 respectively. The passages 3 53, 54 lead to a common discharge chamber 55, Figure 1, whereas the passages .56, :57 lead into the open. The rod 8 connecting ries a driver mem 10 and slots 10 he existin the plungers 2, 3 carber 9 with stops 10, (Fig. 4). Each plunger 2, 3 is provided on the inner surface with a nose 16, 16 respectively having an oblique leading surface, and a strip 19, with noses 20, 21, within the sphere of movement of the sliding member 9, swings on a flat-spring how 18 in a side chamber 17 of the pump body.

The sliding member 9 carries an arm 11, passing through a slit 12 in the pump body and engaging in a recess 13 in a sliding sleeve 14. This sleeve 14 is seated on the control valve 22 which is housed in a working chamber-15 in the pump the valve pistons 23, 24 (of app star shaped cross section) and the valve pistons 25-28. Within, the scope of the stroke of the pistons 2528, which is rather shorter than-that of the sliding member 9, are'situated, on theone hand, the mouths of the inlet passages 29, and outlet passages 31, 32 for; the working fluid, and on the other hand the body,- .with roximately cylindrical 201,936, and in Germany January 27, 1926.

mouths of the passa working chambers l.

The valve 22 also carries two collars 35, 36 and two spiral springs 37, 38 situated between the end surfaces of the sleeve 14 and the valve guides 23, 24 respectively. A strip 41 swinging on a flat-spring bow in a lateral chamber 39 in the chamber 15, is provided with noses 42, 43 projecting into a. longitudinal slit 44, with oblique working'edges 44 in the sleeve 14.

The pump operates in the followin ner:

The workin ges 33, 34 leading to the g mang liquid, supplied from the out side, flows through the passages 30 and 34 into the working chamber 1, below the working plunger 3 and moves the group of working pistons and plungers 5, 3, 3, 2, 4 upwards in the direction of the arrow a. At first, the sliding member .9 takes no part in this movement, being detained by the strip 19, the nose 21 of which is in engagement with the stop l0 of the member 9. 1n the vicinity of its dead point the plunger 3 strikes, by means of its nose 16, entering into the slot 10" against the nose 21 of the strip 19, causing this to tilt and brings the nose 21 out of engagementwith the stop 10. The member 9 is now able to move freely on its rod 8, and shares the further movement of the plunger 3.

The movement of the valve piston is at first retarded, because the collar 36 with which it is connected is checked by the nose 43 of the strip 41. At the same time, the spring 38, situated between'the valve piston 24 and the sleeve 14 is slightly compressed. As soon as the check on the member 9 is relieved and the latter begins to move, the sleeve 14 also moves, in con sequence of its engagement with the nose 11 of the member 9, thereby relieving the tension on the spiral spring and compressing the upper spring 37.

After the sleeve 14 has moved for a short time, the oblique working edge 44 of its 1011- gitudinal slit 44 strikes against the'strip 41 and tilts this latter so that its nose 43 releases the collar 36 and therewith the entire piston group 28, 27, 24, 36, 35, 23, 25, 26. This group is suddenly forced into its upper dead point by the expanding spring 37, and the inlet and outlet passages are reversed, by positive action, atthe same instant thatthe 8, 2, 4 reaches its upper piston group 5, 3 ,lglead point. Shortly beforehand, the mem- {fiber 9 is prevented from arbitrarily returning by the upper nose of the strip 19, so that,

for the time being, the spring 37 is prevented from expanding by the counter movement of the piston group 2, 3. The spring 37 does not expand completely, but remains under slight compression, in order that the piston group may be moved with suilicient force into its dead point in spite of the presence of any impurities in the working medium. The condition of the springs in respect of tension are rendered possible by thestroke of the sliding member 9 being longer than that of the group of valve pistons. 7

As shown in Figure 4, the slide or actuator 9 contains a longitudinal slot 10 into which projects the nose 21 ofthe ledge 19. Just before the piston K engages or strikes against the member 9, the nose 16 enters the slot 10 of the slide or actuator 9 and pushes the. nose 21 away from the stop 10.

When the pistons 55, 3, S, 2, 4 are in the upper dead point, the valve 9 and thepiston group 28, 27, 241, 36, 35, 28, 25, 25, are again blocked, inasumch as the nose 20 of the strip.

19 bears against the stop 10 of 9, and the nose 42 of the strip 11 against the collar At the same time the upper spring 37 is slightly compressed as the result of the stroke of the sliding member 9 and sleeve 14: being longer that that of the valve piston. The down stroke of-the pistons therefore proceeds in the same manner as the up stroke. In order to prevent any braking effect caused by the possible entrance of liquid into-the space between the pistons 2 and 3, one or more bypass channels 58, 59 open into said space. The spring control of the sleeve 14 and strips 19 and 41 may also be effected by springs of other design, or by other elastic means. All the oblique leading surfaces may also be disposed in the opposite direction, and the correspondingly designed noses and stops be subjected to force in the reverse direction. The noses and stops may also be replaced by 1 spring pins, cams or the like.

What I do claim as my invention and desire to secure by Letters Patent is 1. A borehole pump, including a body having an enlarged bore terminating at each end in a reduced bore, two enlarged pistons mounted for reciprocation within the enlarged bore, a stem connecting both pistons and in spaced relation for unitary movement, two reduced pistons, one extending beyond each enlarged piston and movable with said enlarged pistons and mounted in the reduced bores, andactuator slidably mounted upon the stem between the enlarged pistons, means disposed in the path of the actuator to lock the actuator against movement during a part of the pistons stroke, means carried by each piston for releasing said locking means to free the actuator for movement with the istons, and means for controlling pressure uid to and from the enlarged bore to actuate the pistons therein, said latter means being under the control of the actuator.

2. A borehole pump according to claim 1 in which the means for controlling the pressure fluid includes a reeiprocatory piston, and spring propelling and cushioning means, the latter being connected at all times with the actuator and through which the actuator imparts movement to said last piston to control in timed relation the admission of the pressure fluid to the large pistons.

3. A borehole pump, including a body having an enlarged bore with oppositely reduced ends, two operating pistons mounted in the enlarged bore, a stem interposed between and connecting said pistons for unitary action, two reduced pistons one connected to each of the enlarged pistons and operable in the reduced bores, check valve controlled inlets and outlets for the reduced bores, 411d pressure fluid controlling and actuating means slidably mounted upon the stem, the latter including means for being held immovable during the initial movement of the stem and enlarged pistons and to be released to be moved by one of said enlarged pistons.

1. A borehole pump, including a body having an enlarged bore with oppositely reduced ends, two operatively pistons mounted in the enlarged bore, a stem interposed between and connecting said pistons for unitary action, two reduced pistons one connected to each of the enlarged pistons and operable in the reduced bores, check valve controlled inlets and outlets for the reduced bores, pressure fluid controlling and actuating means slid ably mounted upon the stem, the latter including means for being held immovable during the initial movement of the stem and enlarged pistons and to be released to be moved by one of said enlarged pistons, a bore parallel to the enlarged bore and into which operating pressure fluid is admitted, and a reciprocatory double valve mounted in said bore and operably connected with the actuator whereby pressure fluid is controlled in timed relation for admission to and exhaust from the enlarged bore.

5. A borehole pump, including a body ing means slidably mounted upon the stem,

the latter including means forbeing held im movable during the initial movement of the stem and enlarged pistons and to be released .to be moved by one of said enlarged pistons, said body being provided with a bore parallel with the enlargedbore, the opposite ends of which are in communication with the iespecthe ends of the enlarged bore for the introduction of pressure fluid to and the exhaust therefrom, stem mounted in the latter bore for reciprocatory movement, valves mounted upon said stem for controlling the entrance and exhaust ports to the enlarged bores, a sleeve mounted in said bore and operably connected to the actuator, resilient means 10 forming a connecting medium between said determine the action of the valves to exhaust fluid from one end of the enlar ed bore and admit fluid to the other enlar re.

In testimony whereof I aflix my signature.

HERMANN KNAB. 

